Photoshop/AfterEffects: Why are there random transparent blotches from my photo?

So I've been having trouble keying in photoshop, so I just decided to use After Effects' keylight because it works amazing. So i keyed out my image and it looks great, so exported it from after effects as a PNG sequence (Its only one frame). In finder it looks like this

But then as soon as I import it into photoshop it turns into this crazy mess...

If you look closely theres a bunch of weird transparent blotches. Does anyone know what the problem is?

Here's how i exported it if this helps:
Composition>Save frame as>file...
then I put the settings to RGB+ alpha and rendered it.